SIMULATION OF RADIATIVE HEAT FLUX DISTRIBUTION UNDER AN INFRARED HEAT EMITTER

The article deals with a heat radiation model used for heat flux calculation of an infrared heater. In general, we consider a system consisting of a set of objects, whereas a single object could stand for a heater, a reflector or a heated body. Each of the objects is defined by its bounding surface. The presented model applies a 2D restriction of the real system. The aim of a particular simulation is to obtain a heat flux distribution all over the heated body under given conditions such as objects temperature and material properties. Furthermore, the implemented model is used to design a reflector profile to obtain a desired heat flux distribution. The paper presents the implemented model, a comparison of simulated and measured data and an example of reflector design

GENERATION OF TRANSPORT PATHS IN FRACTURED POROUS MEDIA

In this article, a method for generation of transport paths in combined equivalent porous media / discrete fracture network computational meshes is proposed as an alternative to a particle tracking method. It is based on a computation of the functional of the velocity and concentration individually for each element of a mesh. Its functionality is demonstrated on two test cases

A novel approach to modelling of flow in fractured porous medium

summary:There are many problems of groundwater flow in a disrupted rock massifs that should be modelled using numerical models. It can be done via “standard approaches” such as increase of the permeability of the porous medium to account the fracture system (or double-porosity models), or discrete stochastic fracture network models. Both of these approaches appear to have their constraints and limitations, which make them unsuitable for the large- scale long-time hydrogeological calculations. In the article, a new approach to the modelling of groudwater flow in fractured porous medium, which combines the above-mentioned models, is described. This article presents the mathematical formulation and demonstration of numerical results obtained by this new approach. The approach considers three substantial types of objects within a structure of modelled massif important for the groudwater flow – small stochastic fractures, large deterministic fractures, and lines of intersection of the large fractures. The systems of stochastic fractures are represented by blocks of porous medium with suitably set hydraulic conductivity. The large fractures are represented as polygons placed in 3D space and their intersections are represented by lines. Thus flow in 3D porous medium, flow in 2D and 1D fracture systems, and communication among these three systems are modelled together

A model of isotope transport in the unsaturated zone, case study

This work deals with a groundwater flow and solute transport model in the near-surface (predominantly unsaturated) zone. The model is implemented so that it allows simulations of contamination transport from a source located in a geological environment of a rock massif. The groundwater flow model is based on Richards’ equation. Evaporation is computed using the Hamon model. The transport model is able to simulate advection, diffusion, sorption and radioactive decay. Besides the basic model concept, the article also discusses potential cases that could lead to non-physical solutions. On three selected examples, which include, for example, rapidly changing boundary conditions, the article shows the solvability of such cases with the proposed model without unwanted effects, such as negative concentrations or oscillations of solution, that do not correspond to inputs

SIMULATION OF RADIATIVE HEAT FLUX DISTRIBUTION UNDER AN INFRARED HEAT EMITTER

The article deals with a heat radiation model used for heat flux calculation of an infrared heater. In general, we consider a system consisting of a set of objects, whereas a single object could stand for a heater, a reflector or a heated body. Each of the objects is defined by its bounding surface. The presented model applies a 2D restriction of the real system. The aim of a particular simulation is to obtain a heat flux distribution all over the heated body under given conditions such as objects temperature and material properties. Furthermore, the implemented model is used to design a reflector profile to obtain a desired heat flux distribution. The paper presents the implemented model, a comparison of simulated and measured data and an example of reflector design

SIMULATION OF RADIATIVE HEAT FLUX DISTRIBUTION UNDER AN INFRARED HEAT EMITTER

<p>The article deals with a heat radiation model used for heat flux calculation of an infrared heater. In general, we consider a system consisting of a set of objects, whereas a single object could stand for a heater, a reflector or a heated body. Each of the objects is defined by its bounding surface. The presented model applies a 2D restriction of the real system. The aim of a particular simulation is to obtain a heat flux distribution all over the heated body under given conditions such as objects temperature and material properties. Furthermore, the implemented model is used to design a reflector profile to obtain a desired heat flux distribution. The paper presents the implemented model, a comparison of simulated and measured data and an example of reflector design.</p